Collapsible structure

ABSTRACT

A collapsible structure comprising a bottom X-like frame composed of two interpivotted rigid members, and a pair of side X-like frames each composed of two interpivotted rigid elements and each pivotally connected to the bottom X-like frame, the members of each side frame being interconnected for relative movement about two axes of rotation, a foldable handle connected to the interpivotting point of the members of said bottom X-like frame, and means to maintain the structure in an erected position in which the side X-like frames are located in generally vertical planes, release of said means and movement of said handle towards said bottom X-like frame causing relative movement between the members of the bottom X-like frame and between the members of the side X-like frames, and movement of the side frames towards one another, so that said members lie in juxtaposed positions in generally parallel planes. In its application to a baby carriage the structure will carry a collapsible seating unit and wheels and brake/stabiliser assemblies.

United States Patent [191 Firth et al.

[ Nov. 11, 1975 1 1 COLLAPSIBLE STRUCTURE [73] Ass ignee: Lawrence Wilson & Son Limited,

Yorkshire. England [22 Filed: Mar. 4, 1974 [211 Appl. No.: 447,512

[30] Foreign Application Priority Data Dec. 18. 1973 United Kingdom 326/73 [52] US. Cl 280/36 B [51] Int. Cl. B62B 7/08 [58] Field of Search... 280/36 B. 41 A41 B. 47.38; 188/4 R, 20, 110, 143

[56] References Cited UNlTED STATES PATENTS 1.8694205 7/1932 Mahr 280/36 B 2.174.268 9/1939 Kroll et :11. 280/36 B 2.573.106 10/1951 Macip .1 280/41 A 3.024.035 3/1962 Tapioraard 280/36 B 3.217.839 11/1965 Watkins et al. r. 188/4 R 3.390.893 7/1968 MacLaren 280/36 B FOREIGN PATENTS OR APPLICATIONS 669.781 3/1936 Germany 188/4 R 802.132 I 6/1951 Germany 188/4 R Primary Exunziner-Drayton E. Hoffman Assistant Eruminer-Norman L. Stack. .lr. Attorney. Agent. or FirmWolf. Greenfield & Sacks [57] ABSTRACT A collapsible structure comprising a bottom X-like frame composed of two interpivotted rigid members, and a pair of side X-like frames each composed of two interpivotted rigid elements and each pivotally connected to the bottom X-like frame the members of each side frame being interconnected for relative movement about two axes of rotation. a foldable handle connected to the interpivotting point of the members of said bottom X-like frame. and means to maintain the structure in an erected position in which the side X-like frames are located in generally vertical planes, release of said means and movement of said handle towards said bottom X-like frame causing relative movement between the members of the bottom X-like frame and between the members of the side X- like frames. and movement of the side frames towards one another. so that said members lie in juxtaposed positions in generally parallel planes. In its application to a baby carriage the structure will carry a collapsible seating unit and wheels and brake/stabiliser assemblies.

3 Claims. 11 Drawing Figures U.S. Patent Nov. 11,1975 Sheet 1 of4 3,918,734

U.S. Patent Nov. 11, 1975 Sheet 2 of4 3,918,734

U.S. Patent Nov. 11, 1975 Sheet30f4 3,918,734

US. Patent Nov. 11,1975 Sheet4 0f4 3,918,734

COLLAPSIBLE STRUCTURE This invention relates to Collapsible structures, par; ticularly, but not exclusively for baby carriages, invalid chairs and like conveyances.

Collapsible structures for the above purposes are well known, one particular form of structure comprising a bottom X:like frame and a back X like frame in an in clined plane which a e pivotally connected together, the structure including associated members, and the whole is collapsible from an erected condition into what is termed a stick like formation. This known form of structure includes a two part toggle bar or strut, the two parts lying in parallel relationship when the structure is in an erected condition. These two parts are moved relative to one another about a gene ally central pivot point to obtain collapse of the structure, the two parts being intended to be foot operated.

In its application to a baby carriage, the structure is intended to ca ry a seating unit, but because the struc; ture collapses to a stick like formation, such a seat structure can only be formed of a pliable fabric so that the seat structure can fold into thestick-like formation. It is thought that such a seat structure is inadequate and does not provide proper support for the baby or infant using the chair, and the present invention seeks to pro: vide an improved form of collapsible structure for use in for example push chairs a baby carriages, whichstructure because of the manner of collapsing will en: able at least a semi -rigid seating unit to be carried by the structure.

Accordingly, the present invention provides a collapsible structure comprising a bottom X -like frame composed of two interpivoted rigid members, and a pair of side X-like frames each composed of two interpivoted rigid elements and each pivotally connected to the bottom x like frame, the members of each side frame being interconnected for relative movement about two axes of rotation, a foldable handle connected to the interpivoting point of the members of said bot: tom X-like frame, and means to maintain the structure in an erected position in which the side X -like frames are located in generally vertical planes, release of said means and movement of said handle towards said bot:

tom X-like frame causing relative movement between the members of the bottom X-like frame and between the members of the side X like frames, and movement of the side frames towards one another, so that said members lie in juxtaposed positions in generally parallel planes.

Preferably, the members of the bottom Xflike frames are connected to the members of the side X like frames for movement about two axes of rotation so as to en: able the juxtapositioning when the structure is col: lapsed.

The handle will include a handle support to which the handle is pivotally connected, the handle support being connected to the interpivoting point of the members of the bottom X-like frame.

The members of the bottom X -like frame will prefer; abIy be cranked in their interpivoting positions so that the members lie in the same general plane, and the said members will be pivotally connected to the-members of the side like frames by means of U shaped brackets and pivot pins, the U-shaped brackets embracing the members of the side X-like frames.

The means to maintain the structure in an erected position will preferably becarried by the handle support and will comprise pivotable latch means adapted to engage a latch bar carried by the side X-like frames, the latch means preferably including a pivotable safety catch. 7 v I The collapsible structure will carry front and rear pairs of double-wheel assemblies the wheels of each assembly being mounted on a common axle or spindle, each rear wheel assembly carrying a combined stabiliser/brake assembly whicn in an operative position is adapted to raise the rear wheel assemblies clear of a support surface. Each stabiliser/ brake assembly will preferably be spring biassed to an inoperative position.

The collapsible structure will, in its application to a baby carriage, carry a foldable seating unit including an integral head rest portion.

In order that the invention may be more readily understood, an embodiment thereof will now be described, by way of example, reference being made to the accompanying drawings which illustrate the inven tion as used in a baby cariage.

IN THE DRAWINGS FIG. l is a front perspective view of a baby carriage incorporating a collapsible structure according to the invention and showing the structure in an erected conditions;

FIG.-2 is a front elevation of the baby carriage of FIG. -1;

FIG. 3 is an underneath plan view of the baby carriage; FIG. 4 is a side elevation of the baby carriage; FIG. 5 is a rear elevation of the baby carriage;

' FIGS. 6 and 7 are enlarged detailed sectional views of part of the structure of FIGS. 1 to 5 and showing the part in differing positions;

FIGS. 8 and 9 are enlarged detailed sectional views of a further part of the structure FIGS. 1 to 5 and showing the part in differing positions;

FIG. 10 is a side elevation of the baby carriage" and showing the structure in a partially collapsed condition; and 1 FIG. 1 is a top perspective view showing the baby carriage structure in a fully collapsed condition.

Referring to the drawings, and firstly to FIGS. 1 to 5, the baby carriage illustrated comprises a collapsible structure and a seat portion or unit. The collapsible structure includes a bottom X-like frame A, spacedapart X-like side frames B andC, a handle supporting member D and a handle E.

The bottom X-like frame A, when the structure is in an erect position as shown in'FlGS. l to 5, is generally horizontal and comprises first and second interpivoted lightweight tubular members 2 and 4 which are pivotted together by means of a pivot pin 6 so that the members may move relative to one another in substantially the same plane, this being achieved by cranking the members 2 and 4 asindicatd at 2A and 4A.

The side X-like frame B comprises lightweight tubular members 8 and 10 interpivotted by means of a pivot pin 12 and bracket 12A and the side X-like frame C comprises lightweight tubular members 14 and 16 interpivotted by means of a pivot pin 17 and bracket 17A, the brackets 12A and 17A embracing their respective members as shown.

The member 2 is pivotally connected to the member 8 of the side frame B and also the member 16 of the 3 side frame C as follows. A pivot pin 18 secured to a U shaped bracket 20, which embraces the member 8 and which is movably secured thereto by pivot pin 22 connects the member 2 to the member 8, and a pivot pin (not shown) secured to a U-shaped bracket 24, which embraces the member 16 and which is movably secured thereto by a pivot pin (not shown), connects the 7 member 2 to the member 16.

Similarly, the member 4 is pivotally connected to the member 14 of the side frame C and also to the member of the side frame B. A pivot pin 26 secured to a U shaped bracket 28, which embraces the member 14 and which is movably secured thereto by a pivot pin 0, connects the member 4 to the member 14, and a pivot pin 32 secured to a U-shaped bracket 34, which embraces the member 10 and which is movably secured thereto by a pivot pin (not shown), connects the member 4 to the member 10.

The connection of the bottom X-like frame A to the side frames B and C in this manner enables the members of each frame to move relative to one another and also enables the frames to move relative to one another, as will be hereinafter explained.

The pivot pin 6 interconnecting the members 2 and 4 of bottom X-like frame A carries a stirrup 36, the legs 36A and 36B whereof are pivotally secured to cranked ends of members 38 and 40 of the handle supporting member D by means of pivot pins 42 and 44. The other (upper in the drawings) ends of members 38 and 40 are secured to a latching member 46 which will be herein; after be described in detail.

The members 38 and 40 carry a U-shaped stirrup 48, the arms of which are pivotally secured to the arms 50 and 52 of the handle E by pivot pins 54. The arms 50 and 52 of handle E carry a latch bar 56, the ends of which are pivotally secured by brackets 58 and 60 and associatedpivot pins the pivot pin associated with bracket 58 being inicated by reference numeral 62 in FIG. 4 to the upper (in the drawings) ends of members 8 and 14 of side X-like frames B and C. Also secured to the latch bar 56 is a plate 64 having recesses 66 therein for locating the members 38 and 40 in the erected condition of the structure.

The ends of the members 8, 10, 14 and 16 each carry a spindle respectively referenced 68, 70, 72 and 74, the spindles carrying double wheel assemblies 76, 78, 80 and 82, the wheel assemblies 78 and 82 each having a combined stabiliser/brake assembly 84, one of which is shown in detail in FIGS. 8 and 9. Referring to those Figures, in which one of the wheels has been removed for clarity, each stabiliser/brake assembly 84 comprises a hollow triangular member 86 which is pivotally secured to the member 10 of side frame B member 16 of side frame C by means of a pivot pin 88 which carries a coil spring 90, the ends of which engage the triangular member 86 and the associated spindle 70 so that the triangular member 86 is biassed to the position shown in FIG. 8. The triangular member 86 has a recess 92 in one surface which, when the member is in its FIG. 8, i.e., in an inoperative position, embraces the spindle 70 so that the member 86 does not protrude too much beyond the periphery of the wheel assembly. When it is desired to raise the rear wheel assemblies clear of the ground, the triangular member 86 is moved about pivot pin 88 in the direction of arrow X so that the surface 86A rests on the ground. To return the member 86 to its initial position the rear of the baby carriage is raised 46 is pivotally secured to the members 38 and 40 by a pivot pin 94 and the sides 96 and 98 each have a recess therein one such recess being indicated by reference 8 number 100 in FIG. 7, the other such recess being indicated by reference numeral 102 in FIG. 10. Pivotally secured to the centre portionof the latching member 46, by means of a bracket 104 and pivot pin 106, is a safety catch 108 which includes a finger grip portion 108A and which is connected to the pivot pin 94 by a coil spring 110 so that the safety catch is biassed towards the pivot pin 94. FIG. 6 shows the latching member in its engaged position, i.e., when thestructure is in an erected condition, in which it will be seen that the recesses 100 and 102 of the latching member are in engagement with the bar,56 and the safety catch 108 in engagement with the plate 64. With the safety catchin this position, the latching member 46 cannot be moved to release the bar 56 from the recesses 100 and 102 and hence inadvertent movement of the latching member is prevented. To release the latch bar 56 to facilitate collapse of the structure the safety catch 108 is moved in the direction of arrow Y (FIG. 6) about the pivot pin 106 and against the bias of the spring 1 10 to its position shown in chain line, whereafter pressure in the direc tion of arrow Z may be applied to the latching member 46 to cause the latter to release the bar 56, the latching member 46 being moved against the bias of a spring 94A.

The collapsible structure described above has de tachably secured thereto a collapsible seating unit com prising a seat portion 112, back and head rest portion 114 and side portions 116 and 118, the seating unit being supported on the members 8, 10 and 14, 16 of the side frames B and C and by the arms 50 and52 of the handle E. A collapsible foot rest 120 is securedadjacent the forward extremities of the members 2 and 4 of the bottom X-like frame A, and a hand grip122 is.

provided on the handle E. I

To transform the erected baby carrage of FIG. 1 into the collapsed, easily carried form shownin FIG. 1l,the safety catch 108 is moved out of engagement withthe plate 64 whereafter the latching member 46 is disengaged from the bar 56 as previously described. The

handle E is then moved in the direction of Arrow F (FIG. 4). which causes the arms 50 and 52 of handle E to pivot about pivot pins 54 and 62 to assume the position shown in FIG. 10. Further movement of handle E in the direction of arrow F causes interpivotting of the members 8, 10 and 14, 16 of side frames Band Cin vertical planes and the simultaneous interpivotting,

owing to the previously described pivotal connections, of the members 2 and 4 of bottom frame A in a hori.

zontal plane so that the ends of members 2 ,and 4 come closetogether. i

This closing together of the ends of members 2 and 4, due to their connections with the members 8, l0 and l4, 16 of side frames B and C, also causes said side frames B and C to move towards each other with the result that when the structure is fully collapsed the side frames B and C lie in the same general horizontal plane which also contains the collapsed bottom frame A. In the fully collapsed condition illustrated in FIG. 1l,the head rest portion of the seating unit overlies the back rest portion within the handle E overlying the seating unit and the collapsed frames A, B and C.

Thus, we provide a collapsible structure which is easily and readily collapsed in a matter of seconds, and which when collapsed is easily and conveniently carried and stored, and which when erected provides a sturdy support for the seating unit of the baby carriage.

It will be appreciated that the seating unit illustrated in the accompanying drawings and described with reference thereto, may be in the form other'than shown, and indeed that the structure of the invention may be applied to other forms of carriages, not necessarily restricted to use for babies and infants.

We claim:

1. ln a collapsible structure of the type having I. a pair of side frames, each side frame including two members pivotally interconnected intermediate their ends to form an X-like foldable frame, corresponding members of the two side frames being spaced apart and substantially parallel to each other in the erected state of the structure,

2. a bottom frame having two members connected intermediate their ends by pivotal means to form an X like foldable frame, the bottom frame extending between the two side frames and being pivotally connected to the members thereof'whereby folding of the members of the bottom frame is accompawhereby the handle can be moved toward and away from the bottom X like frame, and

d. a latch carried on the handle support, the latch being adapted to engage the latch bar to lock the structure in its erected state.

2. The improvement according to claim 1, wherein the handle is secured to the latch bar in a manner permitting the handle to rotate about the latch bar as an axis.

3. The improvement according to claim 2, wherein the latch bar is pivotally attached to each side frame by means permitting the side frames to pivot relative to the latch bar. 

1. In a collapsible structure of the type having
 1. a pair of side frames, each side frame including two members pivotally interconnected intermediate their ends to form an Xlike foldable frame, corresponding members of the two side frames being spaced apart and substantially parallel to each other in the erected state of the structure,
 2. a bottom frame having two members connected intermediate their ends by pivotal means to form an X-like foldable frame, the bottom frame extending between the two side frames and being pivotally connected to the members thereof whereby folding of the members of the bottom frame is accompanied by folding of the members of the side frames, and
 3. means for locking the structure in its erected state, the improvement wherein the means for locking the structure in its erected state comprises a. a latch bar extending between and attached to a member of each side frame, b. a handle support pivotally connected to the pivotal means of the bottom frame whereby the handle support can be swung toward and away from the latch bar, c. a handle pivotally secured to the handle support whereby the handle can be moved toward and away from the bottom X-like frame, and d. a latch carried on the handle support, the latch being adapted to engage the latch bar to lock the structure in its erected state.
 2. The improvement according to claim 1, wherein the handle is secured to the latch bar in a manner permitting the handle to rotate about the latch bar as an axis.
 2. a bottom frame having two members connected intermediate their ends by pivotal means to form an X-like foldable frame, the bottom frame extending between the two side frames and being pivotally connected to the members thereof whereby folding of the members of the bottom frame is accompanied by folding of the members of the side frames, and
 3. The improvement according to claim 2, wherein the latch bar is pivotally attached to each side frame by means permitting the side frames to pivot relative to the latch bar.
 3. means for locking the structure in its erected state, the improvement wherein the means for locking the structure in its erected state comprises a. a latch bar extending between and attached to a member of each side frame, b. a handle support pivotally connected to the pivotal means of the bottom frame whereby the handle support can be swung toward and away from the latch bar, c. a handle pivotally secured to the handle support whereby the handle can be moved toward and away from the bottom X-like frame, and d. a latch carried on the handle support, the latch being adapted to engage the latch bar to lock the structure in its erected state. 